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Impact Of The Parasitic Nematode Anguillicoloides Crassus On American Eels (Anguilla Rostrata) In Chesapeake Bay, Zoemma Taudel Warshafsky
Impact Of The Parasitic Nematode Anguillicoloides Crassus On American Eels (Anguilla Rostrata) In Chesapeake Bay, Zoemma Taudel Warshafsky
Dissertations, Theses, and Masters Projects
American eels are infected by the introduced parasitic nematode, Anguillicoloides crassus, which can cause significant damage to their swimbladders. Despite the high prevalence and severe damage caused by A. crassus, the population level effects on American eels are not well understood. The prevalence and swimbladder damage in young glass eels and elvers are relatively unstudied, despite the potential for this parasite to cause tissue damage. Additionally, the effects of environmental, temporal, and spatial variables have been debated in previous studies without consensus. Also, the potential for eels to recover from infection and tissue damage has been speculated but not definitively …
Influence Of Structural Complexity And Location On The Habitat Value Of Restored Oyster Reefs, Melissa Ann Karp
Influence Of Structural Complexity And Location On The Habitat Value Of Restored Oyster Reefs, Melissa Ann Karp
Dissertations, Theses, and Masters Projects
In the Chesapeake Bay, < 1% of the historic oyster population remains, and efforts have been increasing to restore oysters and the services they provide. Building reefs that successfully provide ecosystem services–especially habitat and foraging grounds–may require different restoration techniques than those previously used, and success may depend on reef morphology (complexity), location, and environmental conditions. Salinity and habitat complexity are two important factors that may interact to effect benthic communities and predator-prey interactions on restored reefs. The goals of this project were: (1) Characterize the benthic communities on restored oyster reefs in lower Chesapeake Bay, and (2) examine the effects of structural complexity and salinity on benthic communities and predator-prey interactions. A two-year field survey of restored reefs was carried out in four rivers in lower Chesapeake Bay to characterize faunal communities on restored reefs and to quantify the effect of reef complexity on faunal communities. A laboratory mesocosm experiment was conducted to examine the effect of reef complexity on predator foraging. In total, 61 macrofaunal species were identified among all samples, and restored reefs supported on average, 6,169 org/m2 and 67.88 g-AFDW/m2. There were significant differences in the community composition and diversity among the rivers, and salinity was the environmental factor that best explained the observed differences in species composition across the rivers. Salinity and rugosity (i.e., structural complexity) both positively affected diversity, while salinity negatively affected macrofaunal abundance and biomass. Oyster density and rugosity positively affected macrofaunal biomass, and oyster density positively affected mud crab, polychaete, and mussel densities. In the mesocosm experiment, predator foraging, measured by proportion and number of prey consumed, was significantly reduced in the presence of oyster shell structure. However, predators were able to consume more prey when prey density was increased, even in the presence of oyster shell structure. These results combine to enhance our understanding of the benefits of increased habitat complexity for both prey and predators on restored oyster reefs. Increasing complexity worked to increase the abundance, biomass, and diversity of organisms inhabiting restored reefs, and even though predator consumption was reduced in the presence of structure compared to non-structured habitat, predators were able to consume more prey individuals when prey density was increased. Therefore, increasing the structure of oyster reef habitat may benefit prey species by providing refuge habitat, and benefit predators by providing an increased abundance of available prey items.
Assemblage Dynamics Of Larval Fishes In The York River Of Virginia And The Chesapeake Bay, Cindy Marlene Marin Martinez
Assemblage Dynamics Of Larval Fishes In The York River Of Virginia And The Chesapeake Bay, Cindy Marlene Marin Martinez
Dissertations, Theses, and Masters Projects
This thesis developed from the VIMS Larval Fish Monitoring Program, which began in 2007 as part of a study comparing the larval fish assemblages of Chesapeake and Delaware Bays. Ribeiro et al. (2015) analyzed data from the first three years of this time series to describe the temporal variation in the larval fish assemblages. After this initial study was completed (three years in duration), the sampling continued at the fixed station near the mouth of the York River, which was used to represent the Chesapeake Bay. For this thesis, therefore, eight years of data (2007-2015) were available to investigate temporal …
The Effects Of Drifting Fish Aggregating Devices On Bycatch In The Tropical Tuna Purse Seine Fisheries In The Atlantic And Indian Oceans, Julia Snouck-Hurgronje
The Effects Of Drifting Fish Aggregating Devices On Bycatch In The Tropical Tuna Purse Seine Fisheries In The Atlantic And Indian Oceans, Julia Snouck-Hurgronje
Dissertations, Theses, and Masters Projects
Thousands of floating objects, known as drifting fish aggregating devices (dFADs), are released every year by commercial tropical tuna purse seine vessels in the three equatorial oceans to aggregate tuna and increase catch. The escalation in the number of dFADs deployed over the last three decades has caused changes in fishing effort that are poorly reflected in traditional indices of purse seine effort and catch per unit of effort (CPUE). In addition, concerns have been raised regarding the impacts of such high numbers of dFADs being deployed on both catch and bycatch species. I studied two aspects of dFAD deployments …
Reproductive Altruism, Social Diversity And Host Association In Sponge-Dwelling Snapping Shrimps, Synalpheus, Tin Chi Solomon Chak
Reproductive Altruism, Social Diversity And Host Association In Sponge-Dwelling Snapping Shrimps, Synalpheus, Tin Chi Solomon Chak
Dissertations, Theses, and Masters Projects
The diversity of animal social strategies has interested evolutionary biologists since the time of Darwin. Eusociality—the apex of animal sociality—traditionally characterized by cooperative offspring care, overlapping generations and reproductive division of labor, was until recently known only in insects and a few vertebrate species. The independent evolution of eusociality in shrimps in the genus Synalpheus offers a unique opportunity to test the generality of social evolution theories that are based mainly on insects and social vertebrates. The genus Synalpheus is particularly ideal for comparative analysis because their social organizations are highly diverse, yet they share very similar ecology of being …
Influence Of Perkinsus Marinus Infection And Oyster Health On Levels Of Human-Pathogenic Vibrios In Oysters, Lydia M. Bienlien
Influence Of Perkinsus Marinus Infection And Oyster Health On Levels Of Human-Pathogenic Vibrios In Oysters, Lydia M. Bienlien
Dissertations, Theses, and Masters Projects
The eastern oyster Crassostrea virginica is an ecologically and commercially important species whose natural populations have been devastated by overharvesting, habitat destruction, and disease, but the rapid growth of oyster aquaculture has shown potential to restore the economic significance of this species. A key threat to the growth and sustainability of oyster aquaculture is the association of human-pathogenic Vibrio bacteria with product marketed for raw consumption. Two Vibrio species, Vibrio vulnificus and Vibrio parahaemolyticus, are the causes of the highest rates of seafood consumption-related mortality and gastrointestinal illness, respectively. Identification of the factors influencing V. vulnificus and V. parahaemolyticus prevalence …
Alexandrium Monilatum In The Lower Chesapeake Bay: Sediment Cyst Distribution And Potential Health Impacts On Crassostrea Virginica, Sarah Pease
Dissertations, Theses, and Masters Projects
The toxin-producing harmful algal bloom (HAB) species Alexandrium monilatum has long been associated with finfish and shellfish mortalities in the Gulf of Mexico. In the summer of 2007, A. monilatum re-emerged as a bloom-forming species in the Chesapeake Bay. Over the last decade, late summer blooms of A. monilatum have been expanding in range in the lower Chesapeake Bay and have reached record-high densities, particularly in the lower York River. This dinoflagellate species overwinters in the sediments as a resting cyst, and upon excystment under suitable environmental conditions produces blooms the following summer. The research presented here includes the first …
The Reproductive Biology Of Striped Bass (Morone Saxatilis) In Chesapeake Bay, Carissa L. Gervasi
The Reproductive Biology Of Striped Bass (Morone Saxatilis) In Chesapeake Bay, Carissa L. Gervasi
Dissertations, Theses, and Masters Projects
The Striped Bass (Morone saxatilis) is an anadromous finfish that supports a lucrative fishery along the Atlantic coast of the United States and serves as a vital component of estuarine food webs. Once Striped Bass stocks were restored after crashing in the late 1980s, abundance skyrocketed to record levels. Over the past decade however, abundance has steadily declined, concurrent with an outbreak of mycobacteriosis. Disease prevalence is currently >50%, and previous research has demonstrated diseasepositive fish exhibit slower growth and increased natural mortality compared to diseasenegative fish. The purpose of this research was to provide a contemporary description of Chesapeake …
Phylogeny, Ontogeny And Distribution Of The Ribbonfishes (Lampridiformes: Trachipteridae), Jennifer M. Martin
Phylogeny, Ontogeny And Distribution Of The Ribbonfishes (Lampridiformes: Trachipteridae), Jennifer M. Martin
Dissertations, Theses, and Masters Projects
The ribbonfish family Trachipteridae (Lampridiformes) includes three well-defined genera (Trachipterus, Desmodema, and Zu), which are distributed worldwide throughout the pelagic marine environment as with most families of Lampridiformes, drastic changes in morphology occur throughout ontogeny due to extreme allometric growth. Combined with the rarity of specimens, this has led to the description of different life history stages as different species, rather than as part of the ontogenetic continuum of a single species. There is significant uncertainty concerning the ontogeny, distribution, nomenclature, number and phylogenetic affinity of trachipterid and other lampridiform genera.;The first chapter of my dissertation is a taxonomic review …
Mercury Reduces Avian Reproductive Success Through Direct Embryotoxicity Rather Than Altered Parental Behavior, Stephanie Yen Chin
Mercury Reduces Avian Reproductive Success Through Direct Embryotoxicity Rather Than Altered Parental Behavior, Stephanie Yen Chin
Dissertations, Theses, and Masters Projects
No abstract provided.
Habitat Use Of The Declining Wood Thrush In Coastal Virginia, Vitek Jirinec
Habitat Use Of The Declining Wood Thrush In Coastal Virginia, Vitek Jirinec
Dissertations, Theses, and Masters Projects
No abstract provided.
Effect Of Noise On The Social Structure Of European Starlings (Sturnus Vulgaris), Autumn Swan
Effect Of Noise On The Social Structure Of European Starlings (Sturnus Vulgaris), Autumn Swan
Dissertations, Theses, and Masters Projects
No abstract provided.
Natural Variation In Fertility And Gnrh Neurons In A Wild, Natural Population Of White-Footed Mice, Peromyscus Leucopus, Melissa Proffitt
Natural Variation In Fertility And Gnrh Neurons In A Wild, Natural Population Of White-Footed Mice, Peromyscus Leucopus, Melissa Proffitt
Dissertations, Theses, and Masters Projects
No abstract provided.
Phylogenetic Systematics Of The Prickleback Family Stichaeidae (Cottiformes: Zoarcoidei) Using Morphological Data, Todd R. Clardy
Phylogenetic Systematics Of The Prickleback Family Stichaeidae (Cottiformes: Zoarcoidei) Using Morphological Data, Todd R. Clardy
Dissertations, Theses, and Masters Projects
The prickleback family Stichaeidae, as currently recognized, is a diverse group of small (<30 cm TL) eel- or blenny-like marine fishes distributed in intertidal, subtidal, and continental slope waters of the North Pacific, Arctic, and North Atlantic oceans. Stichaeidae is one of nine families within the Cottiformes suborder Zoarcoidei and includes six subfamilies, 38 genera, and about 80 species. However, there are questions regarding the monophyly of the family and its position within Zoarcoidei, due in part to a lack of fundamental descriptive anatomical data for the family. The first chapter of my dissertation describes the osteology of Xiphister, a genus of Stichaeidae that includes two species, X. atropurpureus and X. mucosus, found in intertidal and subtidal waters from southern Alaska to southern California. I describe and illustrate their skeletal anatomy, clarify aspects of their anatomy discussed by previous researchers, and describe for the first time elements such as the hyoid and gill arches, scales, and the development of their lateral line canals. These data establish a foundation for the further anatomical and systematic studies of Stichaeidae, and Zoarcoidei generally. Some members of Stichaeidae, including both species of Xiphister , have multiple lateral line canals on their trunk, which is a feature found in only 15 families of teleostean fishes. In the second chapter of my dissertation, the structure and ontogeny of lateral line canals of both species of Xiphister were studied using cleared & stained specimens and histology. Both species have seven cephalic canals and three paired canals on the trunk located on the dorsolateral, mediolateral, and ventrolateral body surfaces. The ventrolateral canal also includes a short loop across the ventral surface of the abdomen. The trunk canals and four short branches of the infraorbitals that extend across the cheek are supported by small ossified rings. The trunk canals develop asynchronously and separately from the development of scales, suggesting that the ossified rings that support the canals are not modified scales. Results from histology show that neuromasts, the sensory components of the mechanosensory system, are found only in the cephalic, dorsolateral, and mediolateral canals; the ventrolateral canal and its loop lack neuromasts. The evolution and functional role of multiple trunk lateral line canals is discussed. The third chapter of my dissertation examines the phylogenetic systematics of Stichaeidae using 106 morphological characters and 60 terminal taxa, including 30 genera of Stichaeidae, representatives from all eight other families of Zoarcoidei, and additional outgroup taxa. The suborder Zoarcoidei was recovered as a monophyletic group sister to Cottoidei within the order Cottiformes. Within Zoarcoidei, however, the family Stichaeidae was not recovered as a monophyletic family. Only two of the six subfamilies within Stichaeidae, Lumpeninae and Neozoarcinae, were recovered as monophyletic. The high level of homoplasy in the remaining four stichaeid subfamilies, and the inclusion of zoarcoid families nested within Stichaeidae, suggests that the current classification of Stichaeidae does not accurately reflect the evolutionary history of Zoarcoidei.
Seasonal Movements, Habitat Utilization, And Comparative Scale Morphology Of White Marlin (Kajikia Albida) And Roundscale Spearfish (Tetrapturus Georgii), Emily L. Loose
Dissertations, Theses, and Masters Projects
Recent studies have demonstrated that the morphologically similar white marlin (Kajikia albida) and roundscale spearfish (Tetrapturus georgii) co-occur in the western North Atlantic, including the U.S. Mid‐Atlantic Bight. Differences in scale morphology have been proposed as one morphological character to discriminate these species, but a thorough analysis of scale morphology is lacking. Because the validity of the roundscale spearfish was not established until 2006, much of the biological information previously collected for “white marlin” may include data for both white marlin and roundscale spearfish. The objectives of this study were to obtain a better understanding of the movements and habitat …
Rise Of A Floater Class: Behavioral Adjustments By Breeding Bald Eagles In A Population Approaching Saturation, Courtney L. Turrin
Rise Of A Floater Class: Behavioral Adjustments By Breeding Bald Eagles In A Population Approaching Saturation, Courtney L. Turrin
Dissertations, Theses, and Masters Projects
No abstract provided.
Patterns Of Population Structure And Historical Dispersal In Squaloid Sharks: A Species-Level Approach Using Molecular Markers, Ana Christina Pimenta Verissimo
Patterns Of Population Structure And Historical Dispersal In Squaloid Sharks: A Species-Level Approach Using Molecular Markers, Ana Christina Pimenta Verissimo
Dissertations, Theses, and Masters Projects
Squaloids (Order Squaliformes) are a highle diverse group of mostly deepwater habitats (> 200 m). Many species are regularly caught in commercial fisheries worldwide but their low productivity and correspondingly low intrinsic rebound potentials make them particularly vulnerable to population depletion and overexploitation. of special concern to fisheries management and conservation efforts are the spiny dogfish Squalus acanthias, the leafscale gulper shark Centrophorus squamosus and the Portuguese dogfish Centroscymnus coelolepis. These taxa have recently been declared overfished in several parts of each species' distribution but management efforts have been made to recover the "stocks" without a good understanding of the …
Unprecedented Restoration Of A Native Oyster Metapopulation, David M. Schulte
Unprecedented Restoration Of A Native Oyster Metapopulation, David M. Schulte
Dissertations, Theses, and Masters Projects
No abstract provided.
Sexual Dimorphism, Diet, And Body Condition Of Rusty Blackbirds Wintering In Virginia, Andrew John Mcgann
Sexual Dimorphism, Diet, And Body Condition Of Rusty Blackbirds Wintering In Virginia, Andrew John Mcgann
Dissertations, Theses, and Masters Projects
No abstract provided.
The Influence Of Golf Course Landscapes On The Occupancy And Reproductive Success Of Eastern Bluebirds, Marie Louise Pitts
The Influence Of Golf Course Landscapes On The Occupancy And Reproductive Success Of Eastern Bluebirds, Marie Louise Pitts
Dissertations, Theses, and Masters Projects
No abstract provided.
Mate-Guarding In The Australian Zebra Finch, Taeniopygia Guttata: For Males, Protecting Paternity Is More Important Than Extra-Pair Copulations, Leah Catherine Wilson
Mate-Guarding In The Australian Zebra Finch, Taeniopygia Guttata: For Males, Protecting Paternity Is More Important Than Extra-Pair Copulations, Leah Catherine Wilson
Dissertations, Theses, and Masters Projects
No abstract provided.
Deep-Pelagic (0-3000m) Fish Assemblage Structure Over The Mid-Atlantic Ridge In The Area Of The Charlie-Gibbs Fracture Zone, April B. Cook
Deep-Pelagic (0-3000m) Fish Assemblage Structure Over The Mid-Atlantic Ridge In The Area Of The Charlie-Gibbs Fracture Zone, April B. Cook
Dissertations, Theses, and Masters Projects
Only a miniscule fraction of the world’s largest volume of living space, the ocean’s mid-water biome, has ever been sampled. As part of the International Census of Marine Life field project Mid-Atlantic Ridge Ecosystems (MAR-ECO), a discrete-depth trawling survey was conducted in 2009 aboard the NOAA ship Henry B. Bigelow to examine the pelagic faunal assemblage structure and distribution over the Charlie-Gibbs Fracture Zone (CGFZ) of the northern Mid-Atlantic Ridge. This is the first MAR-ECO project aimed specifically at describing diel vertical migration as a distributional phenomenon. Discrete-depth sampling from 0-3000 m was conducted during both day and night in …
Behavioral And Mechanical Particle Selectivity In A Suspension-Feeding Detritivorous Fish, Matthew Kyle Heidman
Behavioral And Mechanical Particle Selectivity In A Suspension-Feeding Detritivorous Fish, Matthew Kyle Heidman
Dissertations, Theses, and Masters Projects
No abstract provided.
Habitat Utilization And Dive Characterization Of Blue Marlin (Makaira Nigricans) And White Marlin (Kajikia Albida) In The Western Atlantic Ocean, Daniel J. Dutton
Habitat Utilization And Dive Characterization Of Blue Marlin (Makaira Nigricans) And White Marlin (Kajikia Albida) In The Western Atlantic Ocean, Daniel J. Dutton
Dissertations, Theses, and Masters Projects
Blue marlin Makaira nigricans and white marlin Kajikia albida (formerly Tetrapturus albidus) are overfished in the Atlantic Ocean, with the vast majority of fishing mortality resulting from the pelagic longline fishery that targets tunas (Thunnus spp.) and swordfish Xiphias gladius. Time series of catch-per-unit-effort (CPUE) data have been fundamental to assessments of blue marlin and white marlin stocks, but these time series have been affected by a shift over time in pelagic longline fishing practices from shallow to deeper sets. One method for adjusting CPUE data for changes in fishing practices is a habitat-based standardization that modifies fishing effort in …
Alternative Substrates As A Native Oyster (Crassostrea Virginica) Reef Restoration Strategy In Chesapeake Bay, Russell Paul Burke
Alternative Substrates As A Native Oyster (Crassostrea Virginica) Reef Restoration Strategy In Chesapeake Bay, Russell Paul Burke
Dissertations, Theses, and Masters Projects
Oyster shell for native oyster reef restoration is scarce in Chesapeake Bay and other estuaries (Chapter 1). Consequently, alternative substrates merit consideration in oyster restoration. This dissertation examines the suitability of shell alternatives, including granite, concrete, limestone marl, concrete modules and reefballs with reef surveys and experiments in the Rappahannock and Lynnhaven Rivers of Chesapeake Bay. Oyster recruitment, growth, survival, density, biomass, condition, and disease stress, as well as reef accretion and persistence, were measured. In the Lynnhaven River, intertidal riprap had a mean density of 978 oysters m-2 (165 g AFDM m-2) and peak densities > 2000 oysters m-2 (Chapter …
Migration Dynamics, Within-Estuary Behaviors And Cardiorespiratory Responses Of Summer Flounder To Selected Estuarine Conditions, Karen M. Capossela
Migration Dynamics, Within-Estuary Behaviors And Cardiorespiratory Responses Of Summer Flounder To Selected Estuarine Conditions, Karen M. Capossela
Dissertations, Theses, and Masters Projects
A comprehensive understanding of migration dynamics, within-estuary behaviors and physiological tolerances of fish is needed to assess and predict future responses of fish to environmental disturbance and to protect habitat necessary for growth and survival. This study adds to current knowledge of summer flounder (Paralichthys dentatus) responses to environmental conditions by (1) examining migration and within-estuarine behaviors of adult summer flounder and (2) establishing summer flounder metabolic requirements and cardiorespiratory responses to variations in hypoxia and temperature. To elucidate use of a southern mid-Atlantic Bight estuary by adult summer flounder, the movements of 45 fish were monitored using acoustic telemetry …
Survival In An Urbanized Landscape: Radio-Tracking Fledgling Eastern Bluebirds (Sialia Sialis) On Golf Courses, Allyson Kathleen Jackson
Survival In An Urbanized Landscape: Radio-Tracking Fledgling Eastern Bluebirds (Sialia Sialis) On Golf Courses, Allyson Kathleen Jackson
Dissertations, Theses, and Masters Projects
No abstract provided.
Female Plumage Coloration In Eastern Bluebirds, Sialia Sialis: Is It A Sexually Selected Trait?, Joanna Kay Hubbard
Female Plumage Coloration In Eastern Bluebirds, Sialia Sialis: Is It A Sexually Selected Trait?, Joanna Kay Hubbard
Dissertations, Theses, and Masters Projects
No abstract provided.
Mud And Mucus: Feeding Selectivity In A Suspension-Feeding Detritivorous Fish, Marie Louise Lammons
Mud And Mucus: Feeding Selectivity In A Suspension-Feeding Detritivorous Fish, Marie Louise Lammons
Dissertations, Theses, and Masters Projects
No abstract provided.
Prey Utilization And Energy Demand Of A Breeding Peregrine Falcon (Falco Peregrinus) Population, Elizabeth Claire Long
Prey Utilization And Energy Demand Of A Breeding Peregrine Falcon (Falco Peregrinus) Population, Elizabeth Claire Long
Dissertations, Theses, and Masters Projects
No abstract provided.